Electric shavers with a slit cutter suitable for cutting relatively long hairs are known for example from EP 0 693 988 B1 and EP 1 410 884 B1. The slit cutters comprise an outer blade as defined above and an inner blade driven by a motor to move in sliding contact with the outer blade. Embodiments of the outer blade known from EP 0 693 988 B1 and EP 1 410 884 B1 have a partially H-shaped configuration with a central web extending substantially along the first axis and with further webs protruding from the central web along a second axis which is substantially oblique or perpendicular to the first axis. As an alternative, it is known that the web has a meander form. In addition, guards may be provided on either side of the slit cutter preventing that skin is pinched in the shaver.
Further shavers with a slit cutter having an elongated outer blade as defined above are known from EP 1 930 135 B1 and US 2010/0175258 A1.
Slit cutters are typically used as long-hair cutters or pre-cutters with which longer beard hairs are to be shortened before the use of e.g. foil-type short hair cutting systems, in order to improve shaving time and the shaving result. It is known that the shaving result can be improved by mechanically preparing the skin that is to be shaved, in order, for example, to lift up beard hairs.
For slit cutters, a proper shaving result requires that hairs enter into the slits between the webs such that they are cut by interaction of the outer blade with an, e.g. oscillating, inner blade. This is especially difficult with hairs having an orientation substantially parallel to the skin. One approach is to reduce the thickness of the outer blade, thereby increasing the number of hairs which may be cut by entering the slits between the webs. However, in addition to the issue of sturdiness of the structure, too thin outer blades can cause skin irritations.